> manufacturers could start selling cars with worse tires to bring down the average.

OEMs do the opposite already because their official MPG ratings are calculated using the OE tires. OE tires are sometimes criticized as prioritizing fuel economy too much at the expense of longevity and performance.

I don’t see a reason that a car manufacturer would be incentivized to help tire manufacturers sell the cheapest tires on the market

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paddy_m 2 hours ago | parent [-]

Car manufacturers watch the cost of every piece of the bill of materials. Cars compete on price, and the assortment of pieces which add perceived value to consumers. Outside of performance and very highend luxury cars, tires are an afterthought to the average car buyer.

	▲	kube-system an hour ago \| parent [-]
		Yes, which is why most optimize tires primarily for price, fuel economy, and NVH, because those are the things which a consumer notices the most when buying a vehicle: "what's the price, what's the EPA estimate, and did I like the test drive?" Some manufacturers even source tires that have lower tread depths than typical replacement tires, in order to decrease noise and increase MPG at the direct detriment to tread life. Tesla is one of the manufacturers that does this, which is one exacerbating factor for their notoriously poor tire life. They literally come with less tire!